# CVE-2026-16237: PostgreSQL INSERT ... ON CONFLICT can read or modify rows despite auto-updatable view WHERE condition

Status: published. Published: 2026-11-12. Updated: 2026-11-12.

Improper protection in PostgreSQL INSERT ... ON CONFLICT on auto-updatable views allows an attacker having INSERT and UPDATE privileges on the view to read and modify every row in the view's base table, via iterated INSERT ... ON CONFLICT DO UPDATE.  This bypasses the view's WHERE condition, whether or not the view is a security_barrier view.  Versions before PostgreSQL 18.7, 17.12, 16.16, 15.20, and 14.25 are affected.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- n/a / PostgreSQL: ≥ 18; < 18.7 (affected, rpm); ≥ 17; < 17.12 (affected, rpm); ≥ 16; < 16.16 (affected, rpm); ≥ 15; < 15.20 (affected, rpm); ≥ 0; < 14.25 (affected, rpm). Source: CNA: PostgreSQL

## Severity and prioritization

- CVSS 3.1: 5.4 (medium); CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N; source: CNA: PostgreSQL

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-424

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://www.postgresql.org/support/security/CVE-2026-16237/ (CNA: PostgreSQL)

## Provenance

- CNA: PostgreSQL: https://www.cve.org/CVERecord?id=CVE-2026-16237; retrieved 2026-11-12; source updated 2026-11-12

Revision: 97bddce596a2af343464197c99d25f5af282e0453472e91205b9aeae153c9d32

Canonical: https://y2.dev/cve/CVE-2026-16237

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